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For the prevention of the stack effect in high-rise buildings in winter, this paper studied a method to cool the shaft by natural ventilation through the opening between the shaft and out air. It was shown theoretically that the shaft is effectively cooled by putting the opening in the lower level of the shaft and thus the stack effect can be effectively prevented. By the calculation for a high-rise building based on the airflow network model and the steady heat balance analysis, it was shown quantitatively that the studied method is effective for general high-rise office buildings and that a careful survey is necessary before introducing this method for the following cases: 1)a case in which the down flow occur in the shaft influenced by the existence of another shaft, 2)a case in which there is no opening to the outside in the upper level of the shaft, 3)a case in which the humidity of the building is high.

This study examined the pressurization smoke control method in the congregated vertical shaft in case of an underground fire. The pressurization smoke control can secure a refuge route by preventing an invasion of smoke to lobby. The congregated vertical shaft exhaust system is a method to shut smoke out of a room. However, it can happen that smoke exhausted from a lower floor leaks from an exhaust opening of an upper floor congregated vertical shaft. Therefore, in this study, for the purpose of grasping the behavior of the leakage of smoke in congregated vertical shaft with pressurization smoke control system, an equation to determine the rate of smoke leakage from the dimension of the building and the behavior of the fire is shown theoretically. Furthermore, a simple method for the design of the shaft setup height and the shaft cross-section area is proposed from the viewpoint of prevention of smoke leakage.

The purpose of this paper is the establishment of the method to confirm at the normal temperature that the pressurization smoke control system is able to block off smoke in case of the fire. A theory is constructed to determine the opening condition of smoke insulation door at the normal temperature which realizes the air flow rate equivalent to that in case of the fire. Although the opening information in the actual building usually does not agree with that in the planning, it is necessary to know the opening information in the actual building. Therefore, in this paper, we propose a procedure to know the opening information by two measurements at normal temperature., and the same time, to judge whether the system is able to block off smoke in case of fire. Moreover the simplified method is proposed for evaluating the performance to block off smoke only from the measurement of one case where the door is fully opened door at the normal temperature. As shown in the example, it would be possible to judge the appropriateness of pressurization smoke control system based on the result of the measurement at the normal temperature.

We present a heating system with thermal storage using a heat pump which supplies heat to the thermal storage installed in a crawl space of a residential house insulated at the foundation walls. We used latent thermal storage materials. This system can charge heat by using cheap nighttime electricity and discharge the stored heat at daytime. We showed equations to determine the air volumes of the heat pump and the ventilator, and equations to determine the phase transition temperature and the amount of the latent thermal storage materials to keep the room setting temperature. We constructed a computer simulation program of this heating system and confirmed the validity of these equations.

‘Crawl-space heating’ is a heating system using the crawl space as a duct for heat transport from a heat pump. The purpose of this study is to grasp the convective heat-transfer coefficient at the slab-concrete surface and the floor-under surface, under the condition of crawl-space heating. When the crawl-space heating is operated, the air velocity in the crawl space is generally 0.05-0.20m/s and the heat transfer is caused by both the forced convection and the natural convection. We measure the convective heat-transfer coefficient by the wind tunnel test. It is revealed that the convective heat-transfer coefficient at the slab-concrete surface is about 1.0-4.0W/m2K and that at the floor-under surface is about 6.0-10.0W/m2K.

In order to evaluate the influences that differences in concrete strength have on hygrothermal behavior in walls, the water vapor permeability, equilibrium moisture content, hydraulic conductivity and thermal conductivity of concrete samples with three different strengths were measured. The following results were obtained:The water vapor permeability and hydraulic conductivity tend to decrease with increasing strength. Movement of both the vapor and liquid phase occurs even at relatively low relative humidity.Furthermore, a method of separating the moisture conductivities into the vapor and liquid phases was proposed and examined by making use of the measured results.

We present a heating system with thermal storage using a heat pump which supplies heat to the thermal storage installed in a crawl space of a residential house insulated at the foundation walls. We used sensible thermal storage materials. This system can charge heat by using cheap nighttime electricity and discharge the stored heat at daytime. It is revealed by experimental studies that thermal behavior of the room is greatly influenced by the heat capacity of the thermal storage. We constructed a computer simulation program of this heating system and showed the ratio of the stored heat for generated heat by the heat pump with the volume of the thermal storage materials. We showed the way to determine the volume of the thermal storage materials and the capacity of the heat pump.